Tamping machine



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April 6, 1937.

E. F. MULLER TAMPING MACHINE Filed Sept. 20, 1933 3 Sheets-Sheet 2 ATT'YApril 6, 193 7.

E. MULLER TAMPING MACHINE 3 Sheets-Sheet 3 .f/YVENTOR: Ernsf FMc/fleFiled Sept. 20, 1933 ATTY Patented Apr. 5, 1 937 UNiTED STATES PATENTOFFICE TAMPING MACHINE tion of Ohio Application September 20, 1933,Serial No. 690,181

3 Claims.

This invention relates to apparatus for injecting tamping material intoa drill hole in a mine after a blasting charge has been placed in suchhole, and effecting the tamping of such material 5 in the drill hole.

One of the objects of the invention is the provision of improved andefficient apparatus adapted to be mounted on a truck traveling on a minetrack and operable under the control of the operatcr by air pressure forintroducing and tamping granular material such as stone dust or sandinto a drill hole after a blasting charge has been placed therein.

Another object of the invention is the provision of mechanism forcontrolling the air supply for the maintenance of proper pressurethereof at all times.

A further object of the invention is the provision of a pressure systemcontrolled clutch for controlling a driving connection between a motorand a driving wheel of a mining machine, which pressure system includesa pump driven by the motor.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. 1 is a plan view of truck-mounted apparatus embodying the presentimprovements;

Fig. 2 is an elevation of the truck-mounted apparatus shown in Fig. 1;

Fig. 2a is a detail view of the control valve between the compressor andthe storage tank;

Fig. 3 is a sectional elevation taken on the line 33 of Fig. 2, lookingin the direction of the arrows;

Fig. 4 is an enlarged elevational view of the controlling mechanism forthe compressor shown mounted on the truck in Figs 1 and 2; and

Fig. 5 is an enlarged sectional elevation of the controlling mechanismfor the compressor shown mounted on the truck in Figs. 1 and 2; and

Referring more particularly to the drawings and especially to Figs. 1and 2, a truckframe 6 .5 is mounted' on wheels I, 1, adapted to travelon a mine track 8. By means of a lever 9 pivoted at H! and connectedthrough the link H to the brake shoe l2, the truck frame may be retardedin its movement along the mine track or held on the latter in astationary position. The lever 9 may be held in brake applying positionby the usual pawl and ratchet mechanism comprising the ratchet H.

An electric motor !3 mounted on the truck 55 frame 6 is connected bymeans of the spur gears I4, 5 to an air compressor l6 which comprises anoperating shaft IT. This shaft extends loosely through a sheave l8 whichmay be connected to the shaft by means of a clutch l9 operable by meansof a lever 26 pivoted at 2| and held in adjusted position by a latch 20on an auxiliary lever 22 pivoted at 23.

When power from the motor I3 is applied to the sheave IS, the endlessrope 24 acts as a belt to transmit rotary movement to the sheave 25 onthe cable reel 26. An electrically insulated cable 2'! is connected tothe electric motor I3, wound on the reel 2t and then extended throughthe winding guiding mechanism 28 to a distant source of electricsupply.A driving sprocket 29 is mounted on the axis of the shaft IT and isconnected by the sprocket chain 30 to a driving sprocket 3! on theforward axle 32 of the wheelmounted truck. By means of a lever 33pivoted at 34 and connected at 35 to a clutch 36, the latter may beapplied to effect the transmission of power from the electric motor [3to the sprocket chain 30 to effect propulsion of the entire machinealong the mine track for transportation in the mine. The lever 33 may beheld in either clutch releasing or clutch applying position by means ofthe latch 22, 33.

The air compressor [6 is connected by a pipe 31 to a compressed airstorage tank 38 which is mounted on the forward end of the truck 6 andsecured thereto by the straps 39, 39, the ends of which are secured tothe upper frame 40 and the lower standards 4|. The air pressure in thetank 38 may be indicated by the pressure gauge 42. The flow ofcompressed air from the compressor l6 through the pipe 31 into thecompressed air tank 38 may be controlled by means of the valve 43. Whenthe lever 44 is in the horizontal position shown in Fig. 2,communication may be established between the compressor l6 and the tank38 with the exhaust port 65 closed. When the lever 44 is moved to avertical position extending below the pipe 31, the latter may be closedand the compressor it connected through the exhaust port to theatmosphere. When the compressor I6 is connected to the atmospherethrough the exhaust port 45, the electric motor l3 will be free torotate either the sheave l8 when the clutch I9 is applied or thesprocket 29 when the clutch 36 is applied; or both the sheave l8 and thesprocket 29 may be operated at the same time. If the air pressure in thestorage tank is below normal, the latter can, if desired, be filled upto normal pressure while traveling from one place to another, thussaving time.

After the truck with the apparatus mounted thereon as shown in Figs. 1and 2 has been transported to a position near a coal face, the brake I2may be applied to hold the truck stationary on the mine track and thelever 54 moved to its horizontal position shown in Fig. 2. The electricmotor I3 may then be operated while the clutches l9 and 35 are released.In order to secure automatic control of the pressure in the tank 38, themechanism shown in Fig. 5 may be provided. The spur gear 55 is mountedin the casing 46 to rotate loosely around the shaft II. A cylindricalclutch element 5i extends from one side of the spur gear l5 and isprovided on its inner cylindrical wall with a plurality ofcircumferentially spaced webs 48 which fit into slots of the clutchdisks 49. The latter alternate with an additional set of clutch disks55, the inner edges of which are provided with slots fitting thecircumferentially spaced webs 5! on the clutch element 52 which is keyedto the shaft 5 l as indicated at 53.

Between the ring 55, which is secured to the spur gear l5 between theclutch elements 4? and 52, and the circular thrust cap 55, the clutchdisks #9 and 55 are arranged as shown in Fig. 5. The central portion ofthe circular thrust cap 55 is cylindrical and cup-shaped to fit over thelefthand end of the shaft H. The outer cylindrical portion 55 of the cap57 forms a cylindrical bearing for the ring 58 which is secured to theclutch element 5? to effect an enclosure for the clutch disks.

A thrust pin 59 is secured to the operating arm 55 by means of the nutiii in position to engage the outer central portion of the cap 51. Anopening may be provided at 62 for the introduction of a lubricant to theshaft [1, thereby lubricating the relative rotation between the thrustcap 55 and the shaft 81. The opening 52 also permits free movement ofthe clutch element 57 relatively to the shaft IT.

The upper end of the operating lever 50 is pivoted at 53 to the bracket54 which is secured to the casing cover 55. The lower end of theoperating lever 55 is provided with a fork 65, the lower ends of whichare pivoted at 55 to a pair of horizontal links 67, 61, the right-handends of which are connected by a cross rod 58 slidable in longitudinalslots 65 in the rear portions of the walls of the cylinder iii.

In the cylinder E5 is an elongated piston H which is adapted to slidealong the cylinder '70 when air under sufficient pressure enters thechamber F2. The right end of the piston H as shown in Fig. 5 engages thetransverse rod 68 which extends transversely of the chamber l3. Inasmuchas the chamber l3 communicates with the atmosphere through the slots 59,the piston 'H is free to slide along this chamber so far as air pressuretherein is concerned.

Movement of the piston ll toward the left along the chamber i2 islimited by the center pin '54 striking against the end wall T5 of thechamber l2. When the pin it engages the wall 75, the left-hand end ofthe piston ii will be adjacent the port it but will not close the same.

In the recess '1'? in the left-hand end of the shaft I! as viewed inFig. 5 is a spring 18 which engages a cylindrical plug 15 bearingagainst the bottom of the thrust cap 51. When the air pres sure in thechamber #2 is relieved so as to free the operating lever 65, the spring18 will release the friction clutch 59, 55.

Mechanism is provided for operating the friction clutch automatically ifsufficient pressure is available from the compressed air storage tank38. The latter is connected by means of the pipe 9i to the chamber 12 ofthe valve structure shown in Fig. 5. When the valve 95 is opened thecompressed air passes through the port 75 into the chamber E2 and movesthe piston ll toward the right to cause the latter to exert pressureagainst the pin 68 to actuate the lever 56 in an anticlockwisedirection. The thrust pin 59 will then exert a pressure against thecentral part of the thrust cap 5?, which pressure is transmitted againstthe friction disks 49 and 50. Since the friction disks 59 are revolvingwith the gear IS, the frictional resistance between the disks 59 and 50will cause the compressor shaft ll to be rotated.

After the friction clutch shown in Fig. 5 has been applied to connectthe motor l3 to the air compressor l6, connection will also beestablished between the motor l5 and the shaft il in Figs. 1 and 2.Therefore, whenever desired, the reel 26 may be rotated by operating thelever 20 to apply the clutch i9. Also when desired the shaft I! may beconnected to the truck propelling sprocket chain 30 by actuating thelever 33 to apply the clutch 35. The clutches l9 and 35 may be appliedindividually or simultaneously and held in applied or released positionsby the latches 25' and 53.

During forward movement of the machine, clutch 35 is applied, but clutchi9 is released to permit free. rotation of the reel 25 to pay out thecable 27 while at the same time the truck propelling mechanism is beingoperated. During rearward travel of the machine both clutches areapplied to effect winding up of the cable on the reel during rearwardmovement of the machine along the mine track. Slipping of the belt 24 onthe drive sheave l8 may be relied on to compensate for the increasingdiameter of the convolutions of cable on the reel.

Furthermore, as above explained, if the air pressure in the storage tank38 falls below normal as indicated by the pressure gauge 52, the valve45 may be opened and the air compressor permitted to operate to restorethe air pressure to normal in the storage tank 35 during transportationof the machine.

The automatic control of air pressure in the compressed air tank 38 maybe understood by referring to Fig. 5 in connection with Fig. 1. When thevalve 95 is opened and the pressure in the storage tank 38 is below apredetermined amount, the spring 8? will push the piston 85 to the leftto establish communication between the pipe 9? and the chamber l2through the port 76. The pin 83 on the piston 88 then abuts against thecap screw 84. The flow of the compressed air through the port 15 intothe chamber 12 will push the piston 'H towards the right therebyapplying the friction clutch as above described and conse quently theair compressor is re-started. It should be noted that the lowestpredetermined pressure in the pressure tank 38 should be high enough tassure suflicient power to apply the friction clutch to effect startingof the compressor.

When a predetermined maximum pressure in the pressure tank 38 has beenreached any excess pressure will move the piston 8| to the right byovercoming the compression spring 87, since the left-hand side of thepiston 8| in the cylinder 82 is in communication through the passageway85 with the pipe 91. It will thus be seen that when the desired maximumpressure in the pressure tank 38 has been reached, the piston 8| willmove toward the right as viewed in Fig. 5 and the port 16 will beclosed. The pressure of the air confined in the chamber 12 will thendiminish by leakage past the piston 1| which fits loosely in thecylinder 10. Consequently the pressure between the disks 49 and 50 ofthe friction clutch will be lessened to allow the discs to slip and thecompressor shaft I1 to stop, preventing any further operation of the aircompressor.

By permitting the valve 95 to remain open, the operation of the aircompressor including its starting and stopping will be entirelyautomatic so long as the electric motor I6 is operating.

Whenever the air pressure in the tank 38 falls so low that the frictionclutch 49, 50 cannot be applied with sufficient pressure, startingoperations may be effected manually by means of the lever 89 which ispivoted at 90 and is provided with a pressure arm 9| in position toengage a crosspiece 92 of the operating lever 60. By starting the motorI3 and manually applying the friction clutch 49, 50, the air compressorI6 may be operated to supply pressure to the tank 38 while the valvelever 44 occupies its horizontal position shown in Fig. 2 with thepassageways of the valve 43 in the positions shown in Fig. 2a.. Aftersuificient pressure has been built up in the tank 30, the valve 8| willbe automatically operated, as above explained. It should be understoodthat the air compressor I'B is connected to the tank 38 through pipes80, 31, and controlled by valve 43. The pressure in the tank 38 may bepredetermined by the setting of the relief valve 96 in accordance withthe reading on the pressure gauge 42 as shown in Fig. 2.

On the truck frame 6 between the air compressor I9 and the pressure tank38 is mounted a large car body hopper 98 for containing the granularmaterial such as stone dust or sand which is to serve as the tampingmaterial. At the bottom of the hopper 98 is an auxiliary circularchamber 99 formed by the hollow dome-shaped housing forming thepartition I00 which has a circular opening IOI in its upper side toreceive the valve I02. The bottom of the chamber 99 is the upper flathorizontal surface N3 of the upper side of the circular plate I04 whichis secured rigidly to the dome-shaped housing I00.

The dome-shaped housing forming the parti- 1 tion I00 is provided withan annular flange I05 which is secured by means of cap screws I08 to thehopper floor plate I01 which is secured rigidly to the laterallongitudinal walls of the hopper 98. It will thus be seen that nocommunication is established between the hopper 98 and the auxiliarychamber 99 except through an opening I0| in the upper side of the domeI00 and this opening is controlled by the valve I02. A vertical rod I08is rigidly connected at its lower end to the valve I02 and the upper endof the rod I08 is pivotally connected at I09 to the lever |I0 shown inFigs. 1 and 3. The lever I I0 is fixed at I II to the rockshaft |I2which is journalled at its ends in the opposite side walls of the hopper98. One end of the rockshaft H2 is provided with an actuating lever II3as shown in Figs. 1 and 2.

The lever arm IIO extends under the upper cross-piece |I4 which isconnected between the upper edges of the opposite side walls of thehopper 98. This cross-piece II4 serves as an abutment to prevent openingof the valve II2 by movement upwardly from the dome I00. By depressingthe lever II3, the valve I02 may be opened by downward movement to itsposition illustrated in dotted lines at I02 in Fig. 3. The tampingmaterial may then flow from the hopper 98 into the auxiliary chamber 99to fill the latter. To facilitate the flow of the tamping material fromthe hopper 98 into the auxiliary chamber 99, a pipe II5 connects thepressure supply pipe 31 to the circular perforated pipe IIE. Byreferring to Fig. 3, it will be seen that the perforations I IT in thecircular pipe I I6 are directed upwardly and angularly toward the valveopening I0| in the top of the housing I00. When the valve I02 isdepressed to establish communication between the hopper 98 and theauxiliary chamber 99, the valve II8 may be opened by the lever II9, asshown in Figs. 1 and 2. The air under pressure will then flow from thetank 38 through the perforations I I1 to aerate the tamping material,evaporate excessive moisture therefrom so as to loosen the granules andmix them to facilitate their flow through the opening I0| into thechamber 93.

After the chamber 99 has been filled with the granular tamping material,the valve I02 is again closed by lifting the lever 3 back to its initialposition. The valve I02 preferably comprises an annular flexible elementI20 of leather, rubber, or

other flexible material which is held against a conical annular seat inthe cone-shaped support I2I by means of the circular plate I22 and thelower screw-threaded end I23 at the bottom of rod I08.

The granular material that flows into the chamber 99 is forced by airpressure through the pipe I24 and the nozzle I 25 for flow into thedrill holes. The branch pipe I26 is connected between the air pressuresupply pipe 31 and the annular chamber I21 which surrounds the dependingannular skirt I28 as shown in Fig. 3. The lower edge of the annularskirt I28 is spaced above the horizontal surface I03 of the bottom plateI04. The housing I00, the skirt I28 and the peripheral support I29together with the annular flange I05 may be in one integral casting andthe support I29 is so shaped as to make an air-tight fit with p thebottom plate I04.

The flow of the compressed air from the pipe 31 through the pipe I26into the annular chamber I21 may be controlled by the valve I30 which isactuated by the lever I3I. A pipe I32 leads from the interior of thechamber 99 into the flexible hose I24.

It will thus be seen that by affording the relatively small auxiliarychamber 99 and closing the same by means of the valve I02 after thegranular tamping material has filled this chamber a predeterminedpressure may be relied on to afford a uniform tamping of the granularmaterial in the various drill holes into which it is directed by theopening of the valve I30 while the nozzle I25 is inserted into the drillholes. When the valve I30 is open compressed air has free flow aroundthe annular air space I21 and thence radially under the circular edge ofthe annular skirt I28. It should be understood that by reason of theangle of repose of the granular material in the chamber 99, suchgranular material will not fill the annular space I21. The annulardistribution of the compressed air radially and inwardly under the edgeof the skirt I28 will effect sufiicient aeration of the granularmaterial to produce a mixture of air and granular material to effectfree flow of the latter outwardly from the chamher 99 through the pipesI32 and flexible hose I24 and thence through the nozzle I25. The nozzleI25 may always be open because as soon as the valve I is closed, theflow through the hose I24 will discontinue although still filled withthemixture of air and granular material. The auxiliary chamber 99 may beof sufiicient capacity to afford operations to tamp a plurality of drillholes before it is necessary to re-open the valve I02 to re-fill thechamber 99.

The diameter of the nozzle I25 should be relatively smaller than thediameter of the drill hole so as to fit loosely in the latter andprovide for escape of air from the drill hole during the tampingoperation. Due to the expansion of the air while traveling through thehose and the nozzle, the tamping material receives its acceleration andfinal velocity when emerging from the nozzle.

The greater the final velocity of the tamping material, the moreeffective will be the tamping action. Therefore, sufficient clearancebetween the outer surface of the nozzle and the drill hole should beallowed to permit free escape of the air while the tamping material islodged at the inner end of the drill hole.

, As above explained, this tamping operation may be regulated by havingthe pressure in the tank uniform and confining the granular material inthe chamber 99 by the closure of the valve I02. When the air pressure isexerted in the chamber 99 the flexible element I20 tends to expandradially to hold the opening IGI tightly closed. Therefore the onlyescape for the compressed air in the chamber 99 will be through the pipeI32.

After holes have been drilled in a coal face, the cuttings may becleaned out by means of the nozzle I 33 connected to the outer end of aflexible hose I34 which communicates with the compressed air supply pipe3'I. The flow of the compressed air from the pipe 31 through the nozzleI33 may be controlled by the valve I3? actuated by the lever I31. Afterthe drill holes have been cleaned and the blasting charges inserted, thespaces in front of the blasting charges may be F filled as aboveexplained with the granular material and uniform tamping thereof securedso as to more effectively predetermine the action of the blasting downof the coal tosecure the maximum amount of lump coal and a minimumamount of slack, in accordance with the hardness of the coal and theamount of blasting material used in the particular system of arrangementof drill holes being employed.

During transportation of the machine shown in Figs. 1 and 2 to and fromthe places where the blasting operations are to be carried on, theflexible sections I34 and I24 of the hose for the nozzles I25 and I33may be supported on the horizontal plate I35 at the forward end of themachine, while the operator may stand on the supporting platform I36 atthe rear end of the machine in position to control the clutch I9 whilethe reel 26 is being rotated to permit paying out of the electric cable21 which is connected to a distant source of electric supply for theelectric motor I3. The operator while standing on the platform I36 mayalso operate the controller for the electric motor I3 and the brakelever 9. When the machine reaches the place in the mine Where blastingoperations are to be carried on, the forward extension of the truckframe beyond the forward axle 32 will permit the forward end of themachine to be located as close to the working face of the coal vein asthe mine track 8 will permit and therefore relatively short lengths offlexible hose I24, I34 for the nozzles I25 and I33 will be sufficient.

Certain features of the apparatus herein disclosed and particularly thehopper 98 and the auxiliary chamber 99 illustrated in detail in Fig. 3are disclosed and claimed in the application of Nils D. Levin and ErnstF. Muller, Serial No. 618,098, filed June 20, 1932.

Obviously those skilled in the art may make various changes in thedetails and arrangement of parts without departing from the spirit andscope of the invention as defined by the claims hereto appended, and Iwish therefore not to be restricted to the precise construction hereindisclosed.

Having thus described and shown an embodiment of my invention, what Idesire to secure by Letters Patent of the United States is:

1. In a truck mounted tamping apparatus, the combination with a truckadapted to travel on a mine track, of an air compressor on said truckcomprising a shaft, a motor for driving said compressor and said truck,a clutch adjacent one end of said shaft for connecting said motorthereto, and a clutch adjacent the other end of said shaft forconnecting said shaft to a wheel of the truck.

2. In a truck mounted tamping apparatus, the combination with a truckadapted to travel on a mine track, of an air compressor on said truckcomprising a shaft, a motor for driving said compressor and said truck,a fluid storage tank connected to said compressor, a clutch adjacent oneend of said shaft for connecting said motor thereto responsive to thepressure of said tank, and a clutch adjacent the other end of said shaftfor connecting said shaft to a wheel of said truck.

3. In a truck mounted tamping apparatus, the combination with a truckadapted to travel on a mine track, of an air compressor on said truckcomprising a shaft, a motor for driving said cornpressor and said truck,a compressed air storage tank connected to said compressor, a clutch forconnecting said motor to said shaft, a clutch for connecting said shaftto a wheel of said truck, saidfirst mentioned clutch being actuated byair in said storage tank and being engaged and disengaged responsive topressure changes therein.

ERNST F. MULLER.

